常見例句用作名詞 (n.)This was the result from the large-scale regression in the Late Ordovician.這是奧陶紀(jì)晚期大規(guī)模海退的結(jié)果。Major hydrocarbon source rocks are in the Cambrian and Ordovician.寒武-奧陶系烴源巖是該區(qū)主力烴源巖; 返回 Ordovician